Professor Flead is a necromancer, from the time when a necromancer could blast people with Black Fire to get them to move. Although he has been dead for nearly 300 years at the time of Making Money, you can't take the romance out of the necromancer. He is extremely excitable at the sight of young ladies, hemlines having risen since his death. His flirtation with Adora Belle Dearheart is quite distressing to Moist von Lipwig, her boyfriend - so much so that he finds a convenient way to install Professor Flead in a location Adora Belle will never discover. He is described in Making Money by Moist as a 300 year old letch to which Adora replies, "I think you mean lych". Pratchett puns on the words as a "lych" is an old English word for a corpse and a "letch" is short for a letcherous person. Flead is also referred to as being "dead at the moment" suggesting that this state is changeable, a concept which resonates with Douglas Adams' series The Hitchhiker's Guide to the Galaxy where the rock star Hotblack DeSiato takes a year off dead for tax purposes. In the novel, he is described with "little strings of saliva vibrat(ing) in his mouth like the web of a very old spider". This description is clearly designed to remind the reader of the poem by Mary Howitt (1799–1888), published in 1828, The Spider and the Fly, in which the spider leads the fly to her doom with, "'Will you walk into my parlour' said the spider to the fly." The poem, while appearing to be about a spider and a fly is clearly about seduction, an older rake and a young virgin.
Flead is an expert on the language of the empire of Um, which perished sixty thousand years ago.
At the conclusion of Making Money, he is (per his request, and the manipulations of Moist) insorcised into (that is, made to haunt) the Pink PussyCat Club. He currently haunts seat seven (front row, centre). This has served only to benefit the club, as all rabble-rousers, bad tippers and general good-for-nothings promptly find themselves thrown out on their backsides even without the intervention of the club bouncer. The management has concluded that the peace and (relative) quiet is worth the loss of a single seat's fee. Even though he is a letch he can cause no problems for the girls at the club, which maintains a strict 'no touching' policy because, he is also a lych (corpse) and being dead means he cannot touch anything even if he wants to.